|11-14-2012 02:15 AM|
|Gold Finger||Yes, interesting. Not stupid. I believe you are getting more net CO2 and, perhaps more importantly, more O2 into your water. Get the bubbles small enough (microbubbles) and everything will enter the water. It may not be a lot of CO2, maybe even a completely negligible amount, but it seems to me like it should be some amount higher than you would get atmospherically from a turbulence source. Maybe you are right, but higher O2 is my guess as to any true connection to less algae there may be. Having a non CO2 tank, I used to give this stuff a lot of thought. I settled on having all of my tank water leave the tank and go to the sump through surface skimming. This way the surface exchange membrane a) is always spottless and therefore as permeable as possible, and b) is moved back into circulation and quickly replaced with fresh, CO2 hungry water from below. Perhaps it is moot for me now as I am using Excel, but perhaps not. Any advance in higher CO2 levels for non injected tanks is a good thing. Interesting in any case.|
|11-13-2012 01:15 AM|
|chibikaie||Ooooh, this does look neat. I might have to try this, although arguably my goldfish tank needs more filtration as well as circulation.|
|11-13-2012 12:26 AM|
|ptr||In my case, I have observed a better growth, less algae, and overall better plant health with this setup. I would love to have other TPT users try the same thing and post their results.|
|11-12-2012 11:37 PM|
a) CO2 depleted water from lower in the tank is being brought to the surface.
b) larger surface area.
So, comparing 'no water movement' to 'large bubbles' there is a net increase in CO2 for the plants.
But in this tank there is already quite a bit of water movement from the filters. So the increase in vertical water movement may not be needed.
When the bubbles are being broken up this way, the Koralia is chopping them into little bubblets (if there is such a word) AND is sending them horizontally through the tank.
100 little bubblets have more surface area than one giant bubble, so there may actually be some gas exchange happening while those bubblets are in the water.
Also, little bubblets may stay submerged longer. Maybe not a lot longer, but some may be getting caught under the leaves and so on. The whole bubblet might end up disappearing!
I am not sure how tons of little bubblets compare to the same volume of large bubbles when it comes to surface agitation. If each bubblet creates a 1mm wavelet, but each giant bubble creates a 5mm wavelet plus some splash... but there are a lot more little bubblets...
|11-12-2012 06:28 PM|
Hoppy, thanks for setting me straight. I guess I misinterpreted something I read in the past.
One thing though, if an aquarium were getting its CO2 from only atmospheric exposure (ie, surface exchange and bubbles from an air pump), would the gain and the loss not be pretty much equal?
|11-12-2012 05:59 PM|
|ptr||Well actually, you get less surface disturbance compared to having the sponge filter on its own, since most of the bigger bubbles don't get a chance to reach the surface.|
|11-12-2012 05:48 PM|
|11-12-2012 05:07 PM|
The tank (a 60g tall) also has an aquaclear 110 so there's really plenty of filtration. However, without the Koralia there are a still a few dead spots, hence the additional circulation.
Maybe the tank is just healthy because of the heavy oxygenation.
|11-12-2012 05:02 PM|
Sorry, was a bit confused about the use of the Koralia pump. I took it that the entire reason for the pump was to just break up the bubbles coming from the sponge filter.
I'm just wondering, what is your reasoning for increasing circulation over increasing filtration?
I run a sponge filter and a Rena XP2 canister in a 40b and it is almost too much circulation in that tank. I have another 44 hex tall tank that I keep angles in and I have to turn down the penn plax 700 canister output to not blow out the angels with too much circulation and I run a sponge as well on that tank to increase filtration as I do not feel that I am getting enough water exchange with the restricted flow I have set up on that tank.
I personally, could not see adding more circulation but do like having the extra filtration on the cheap.
|11-12-2012 04:48 PM|
|ptr||Well I would be running the koralia anyway for circulation in the tank. It's simply about its positioning (right above the sponge filter).|
|11-12-2012 04:45 PM|
I'm not an expert in any form regarding CO2.
IMO breaking up the bubbles from several larger ones to several smaller ones is just wasting electricity to run the Koralia.
I can see some points for the argument that smaller bubbles of the gasses coming from the sponge filter creates a bigger diffusion similar to using an air stone with a CO2 system but I don't think you are adding any NEW CO2 to the mix, just making smaller AIR bubbles. Yes, there is some CO2 in AIR but you will not be adding any additional CO2 by what you are doing currently.
|11-12-2012 04:41 PM|
Oxygen diffuses into water much easier than CO2, so being that you are only injecting ambient air into the tank, the majority of the surface area in contact with the air is being used to absorb o2 with vary lilttle contact with CO2. Also, you may actually be causing more CO2 to offgas the tank by causing turbulance at the surface.
Anyway regardless of the true results, I personally would not like to see all the bubbles floating throughout my tank. It looks ugly to me.
|11-12-2012 04:41 PM|
|ptr||Well yes, especially if you're talking about pressurized. But it would be pretty cool if it could be a viable alternative to yeast-based methods.|
|11-12-2012 04:38 PM|
|acitydweller||hmm id give it a shot though its likely less potent than direct co2 injection|
|11-12-2012 04:31 PM|
The video below shows an experiment with a sponge filter, where the big air bubbles are being spliced into thousands of tiny bubbles by a small Koralia circulation pump. The (possibly stupid) idea is that, there is 0.04% co2 in the air, which means the equivalent of 1 bubble every 2500 (of course the gases are mixed, but you get the idea). With the sponge filter pumping at least 10 huge bubbles per second, it means the equivalent of one huge co2 bubble every 4 mn. Not spectacular, but still, every little bit counts... and as you can see, there is no sign of algae, and all the plants are thriving, even the blyxa.... whereas in my other tank, that doesn't have the same system, plants are having a much harder time.
So what do you experts think ? Am I just being lucky, or is this indeed getting some more CO2 into the tank ?